A negative direct antiglobulin test with strong IgG red cell autoantibodies present in the serum of a patient with autoimmune haemolytic anaemia.
The case is presented of a boy with an autoimmune haemolytic anaemia of 10 years duration. He had a positive direct antiglobulin test with IgG and complement detected on the red cells and with IgG autoantibodies in the serum. During a recent episode of severe haemolysis, the Hb level fell to 3.8 g/dl and the direct antiglobulin test became negative although his autoantibodies still reacted with all the red cells in a panel. The serum reacted more strongly with C- and e-positive cells. The Rh phenotype of the patient was CcDee as it had always been. Possible explanations of the unexpected findings are discussed.
D000293:Adolescent; D000744:Anemia, Hemolytic, Autoimmune / Q000276:immunology*; D000918:Antibody Specificity; D001323:Autoantibodies / Q000032:analysis*; D003298:Coombs Test; D004912:Erythrocytes / Q000276:immunology; D006452:Hemoglobinometry; D006461:Hemolysis; D006801:Humans; D007074:Immunoglobulin G / Q000032:analysis*; D008297:Male; D012204:Rh-Hr Blood-Group System / Q000276:immunology
D001323:Autoantibodies; D007074:Immunoglobulin G; D012204:Rh-Hr Blood-Group System